Captivate 6 generated content issue on Microsoft Edge

I'm loading generated Captivate 6 html files via iframe in a Modal. When the user first visits the page and clicks to open the Modal, the captivate iframe content loads correctly.

There's a loader for a brief second then the content shows.

Now if the user exits the Modal and try re-opening the Modal, the Modal loads quite alright but the captivate content in the iframe just doesn't display. I can see the captivate loader shows up but the content never shows after. This behavior is very inconsistent i.e if i close and re-open the Modal 10 times, it shows up correctly for 3/10 times.

This only happens in Microsoft Edge.